The present invention relates to developing machines for exposed photosensitive material, especially convoluted webs of exposed photographic paper. More particularly, the invention relates to improvements in apparatus for processing cassettes for webs of exposed photosensitive material and their contents prior to introduction into the developing unit proper of a photographic developing machine.
In presently known developing machines for photographic paper (examples of such machines are so-called LABOMATOR 5 ZOLL machines manufactured by the assignee of the present application), a cassette which contains a supply of convoluted exposed photographic paper web is placed onto a feed table and the leader of the web (such leader extends from the cassette) is advanced through a channel in the feed table and into a dark chamber below the feed table where the leader is clamped to a threading strip or pull tape. The latter serves to advance the leader through the tanks of a developing machine. A drawback of presently known apparatus for processing cassettes which contain exposed photographic paper or the like is that cassettes of varying sizes cannot be alternately positioned at one and the same location above the feed table. The term "varying sizes" is intended to denote all dimensions or parameters of cassettes for webs of different lengths and/or widths. Attempts to enchange the versatility of conventional apparatus include the provision of several feed tables each having a channel or infeed passage of different length, namely, a channel which permits the passage of a web having a given width. Thus, if a first cassette containing a supply of relatively narrow web is to be followed by a cassette which stores a supply of wider web, the previously used feed table must be replaced with a different feed table. This is a time-consuming operation and the supply of spare feed tables occupies a substantial amount of space. Moreover, frequent replacement of feed tables enhances the wear upon their edges and other portions so that such tables are likely to permit light to penetrate into the chamber therebelow after a relatively short interval of use. The same applies for sealing element (e.g., elastic light-intercepting lips or the like) which are normally interposed between an interchangeable feed table and its support.